The present invention relates to a multi-color pen recorder suitable for use in devices such as X-Y plotters, graphic printers, alphanumeric printers and the like.
Recently, personal computers are becoming popular and are being used even in the home. It is also a current tendency that recording devices such as CRT (Cathode Ray Tube) used in combination with personal computers are designed and constructed to make a color display of graphs, patterns or characters.
However, only few proposals have been made hitherto as to recording devices which can make color recording for permanent preservation of the characters or data as the result of operation of the personal computers. The multi-color recorders hitherto proposed are generally expensive and large-sized and, therefore, are not suitable for use in combination with personal computers.
More specifically, a multi-color ink-jet type printer, which is one of typical multi-color recording devices proposed hitherto, is still too expensive and has an impractically large size. Also, an X-Y plotter which is another example of conventional multi-color recording devices has a large size and complicated construction. Namely, as shown in FIG. 1, the X-Y plotter has a carriage 2 holding a single pen and mounted on a slide arm 1 for free sliding movement in X direction. The slide arm 1 in turn is mounted for free sliding movement along a stationary arm 4. For effecting a multi-color recording, the slide arm 1 and the carriage 2 are driven to return the pen 3a presently held by the carriage 2 to the pen-holding section of the stationary arm 4 and then the slide arm 1 and the carriage 2 are driven to make the carriage 2 hold a pen of another color, e.g. a pen 3b. This conventional system thus requires a complicated structure and control for the changing of the pen, and an impractically large space.
To avoid this problem, there has been proposed another structure in which as shown in FIG. 2, a slide arm 7 holding a carriage 6 for free movement in X direction is movable in Y direction along the stationary arm 8, while the carriage 6 carries a plurality of pens 5a, 5b and 5c, thereby to eliminate the troublesome changing operations of pens. This arrangement, however requires that the carriage 6 is equipped with actuators such as solenoids for respective pens, in order to project the desired pen independently toward the recording paper, although the changing operations of pens are eliminated. This hinders the reduction of the size and weight of the carriage 6, and requires a function for controlling the position of the carriage 6 in relation to the positions of the pens, because pens occupy different positions on the carriage 6.